JimsCAL: We don't have any regs on that down here - or at least none that would apply to me besides "do anything stupid and we'll bust your a$$.."
There is a very good reason for the regulation. Fittings on the bottom and sides of fuel tanks at some point will leak, hoses crack, clamps vibrate loose, etc. And fuel ends up in the bilge and other places you don't want it. I would not do it even if there isn't a regulation against it.